Hossain M L, Haider K, Chowdhury T A, Mosihuzzaman M
Department of Chemistry, University of Dhaka, Bangladesh.
J Diarrhoeal Dis Res. 1993 Jun;11(2):93-6.
Six different prepared mutant strains of Shigella dysenteriae type 1 with various combinations of 'core' plasmids of 140, 6, and 2 Mdal, were cultivated separately and their lipopolysaccharide (LPS) samples were isolated, which on delipidation afforded polysaccharides and oligosaccharides. The LPS and prepared O-antigen polysaccharides were subjected to acid hydrolysis, and the constituent sugars were analysed by paper chromatography and gas liquid chromatography (GLC), using CP Sil 8 CB fused silica capillary column equipped with a flame ionization detector. The mutant strains, harbouring the 6 Mdal plasmid, contained rhamnose, galactose, and N-acetyl glucosamine in their O-antigen polysaccharides with a minor variation in the relative proportions of these sugar constituents as compared to those of the control strain. The sugar composition of the O-antigen polysaccharides prepared from the mutant stains, without the 6 Mdal plasmid but containing 2 or 140 Mdal plasmid, contained galactose and N-acetyl glucosamine but no rhamnose. However, mutant strains with none of the core plasmids contained traces of rhamnose and were devoid of N-acetyl glucosamine, but contained heptose. These results suggest that 6 Mdal plasmid is essentially required for the complete synthesis of O-antigen polysaccharides. However, the 140 and 2 Mdal plasmids might also have an association with synthesis of carbohydrate composition of the O-antigen in S. dysenteriae type 1.
分别培养了六株不同的痢疾志贺氏菌1型制备突变株，它们带有140、6和2 Mdal的各种“核心”质粒组合，并分离出它们的脂多糖（LPS）样本，脱脂后得到多糖和寡糖。对LPS和制备的O抗原多糖进行酸水解，使用配备火焰离子化检测器的CP Sil 8 CB熔融石英毛细管柱，通过纸色谱法和气液色谱法（GLC）分析组成糖类。携带6 Mdal质粒的突变株在其O抗原多糖中含有鼠李糖、半乳糖和N - 乙酰葡糖胺，与对照菌株相比，这些糖成分的相对比例略有变化。从不含6 Mdal质粒但含有2或140 Mdal质粒的突变株制备的O抗原多糖的糖组成含有半乳糖和N - 乙酰葡糖胺，但不含鼠李糖。然而，没有任何核心质粒的突变株含有微量鼠李糖，不含N - 乙酰葡糖胺，但含有庚糖。这些结果表明，6 Mdal质粒是O抗原多糖完全合成所必需的。然而，140和2 Mdal质粒可能也与痢疾志贺氏菌1型O抗原的碳水化合物组成合成有关。
